In such double twist frame which is known (from German Auslegeschrift 2 130 621) the upper closure wall is arranged above the balloon thread guide and the lower closure wall is arranged below the whorl and the driving belt. The side walls extend from the lower to the upper closure wall and thus completely enclose the spindles. For the performance of servicing work at least a part of the side wall associated with each spindle is adjustable. The closure walls and side walls consist of sound reflecting and/or sound absorbing material. In this manner there is obtained, in the first place, protection of the attendant personnel against noise. At the same time however the channel enclosed by the closure walls and side walls is connected to a suction device. Thereby, fly occurring from the twisting is sucked away and soiling of the frame is prevented.
Owing to the complete encapsuling of the double twist thread twisting spindles a plurality of flaps associated with each spindle are necessary in order that servicing work such as threading, removing broken threads and so on may be performed at the spindle. This plurality of flaps and rotatable casing parts however increases the cost of the frame considerably and also makes impossible the use of an automatic service carriage for performing the work of threading, removal of broken threads and the presentation of the thread. Moreover, in the case of this known double twist frame conditioning, viz. moistening of the thread is possible only by conditioning the whole of the space in which the frame is located. Moistening of the thread favours the twisting operation and reduces the formation of fly.
It is known (from German Offenlegungsschrift 2,356,562) to feed conditioned air to supply bobbin by means of a blower nozzle directed towards the spindle. Beneath the storage disc of the spindle, in this known device, there is arranged a suction nozzle for sucking away the fly. However, this suction nozzle can only collect fly that reaches its direct vicinity. It has been established that the air is heated relatively strongly by the heat produced in the region of the spindle drive. This heated air then rises in the balloon limiter as in a chimney. There results a strong upward current of air, assisted by the rotation of the spindle and the balloon of thread in the balloon limiter, by which the fly is conveyed upwardly away from the suction nozzle. Moreover, owing to the friction of the thread on the inner wall of the balloon limiter, further fly results which is not gathered by the suction nozzle.
The invention is based on the problem of providing a double twist thread twisting frame of the type mentioned initially, which whilst avoiding the above-mentioned disadvantages is simpler in construction and in which the spindles are accessible from above, so that an automatic service carriage can be used, and in which the fly is removed to a large extent and which also permits direct conditioning of the material being supplied.
In accordance with the invention this is achieved in that the upper closure wall is arranged approximately at the level of the upper rim of the balloon limiter and in the region of each balloon limiter has a circular opening coaxial therewith, that the upper rim of the balloon limiter and/or the circular opening is somewhat smaller in diameter than the part of the balloon limiter located beneath it, and there is provided on the balloon limiter in the region beneath the upper closure wall a suction opening connected to the internal space of the channel, and that above each balloon limiter there is provided a blower tube known in itself directed towards the spindle and connected to a pipe extending in the longitudinal direction of the frame, by which nozzle conditioned air is fed to the supply bobbin.
By arrangement of the upper closure wall at the level of the upper rim of the balloow limiter the spindle is freely accessible from above. In this way flaps and other cladding parts become unnecessary, so that the frame is of simpler construction. Moreover, the free access permits the use of an automatic service carriage. At the same time owing to this construction blower nozzles may also be used which blow the conditioned air directly in the direction of the supply bobbin. In this way conditioning of the whole frame shop can be avoided and also the material being supplied does not need to be previously conditioned in a special conditioning space. The intensive conditioning of the supply material also has the advantage that the formation of fly is reduced. At the same time, with the novel double twist frame very good removal of fly is achieved. Since the twisting spindle is completely surrounded, in the region of the lower rim of the balloon limiter and also of the storage disc, by the channel formed by the upper and lower closure walls and the side walls, an initial sucking away of the fly takes place there. Fly that is carried along by the upwardly directed air current in the balloon limiter and which is present in the balloon limiter itself is to a considerable extent thrown outwardly to the wall of the balloon limiter by the rotating thread. Since the upper rim of the balloon limiter or the circular opening is smaller in diameter than the parts of the balloon limiter located beneath it, and since moreover there is provided in the upper region of the balloon limiter beneath the upper closure wall a suction opening in communication with the internal space of the channel, the fly is to a large extent sucked away through this suction opening. Furthermore, the heat generated continuously at the spindle bearing and at the whorl is removed by the sucking away of the air surrounding these parts. This avoids the effect that the heated air in the balloon limiter rises upwardly, carries fly with it and also dries out the previously moistened thread. In this manner only a very small quantity of fly occurs in the balloon limiter itself, and can at once be removed owing to the above-mentioned design and the suction at the upper rim of the balloon limiter.
Advantageously, the lower closure wall is arranged tightly between the storage disc and the whorl. In this manner the air heated at the whorl is kept away from the other spindles.
In order that the spindle may also be serviced in the region of its storage disc, or be accessible at that place for the corresponding servicing parts of a service carriage, flaps are preferably provided in the side wall beneath the balloon limiter in the region of the storage disc. These flaps are advantageously pivoted at their lower edges and tiltable inwardly. They may extend over a plurality of spindles.